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International Journal of Legal Medicine

, Volume 127, Issue 1, pp 185–194 | Cite as

Non-invasive visualisation and volume estimation of maggot masses using computed tomography scanning

  • Aidan Johnson
  • Melanie Archer
  • Lyndie Leigh-Shaw
  • Matthew Brown
  • Chris O’Donnell
  • James Wallman
Original Article

Abstract

There is limited understanding of the actual temperatures that maggots experience during growth. The impact of maggot mass heating on their growth rates cannot be properly factored into maggot growth rate models, thus limiting the accuracy of forensic entomology estimates. One of the major factors contributing to mass heating is the mass size; however, measuring mass volume is problematic as masses quickly become disturbed when probing them to measure their depth and width. Furthermore, many masses are deep within the body cavity and are inaccessible. This study examined the development of a non-invasive means for measuring mass volume using computed tomography (CT) scanning. It was found that CT can be used to visualise and measure the volume of maggot masses, and a series of rules for doing so were established. The level of agreement between mass measurements made by four ‘judges’ using CT volumetric analysis tools produced excellent reliability (ICC > 0.95). This high level of reliability was maintained when applied to masses of different sizes in experimental cups of meat and natural masses of mixed species on human bodies. Entomological features of mortuary CT scans are now routinely reported in forensic entomology casework in Victoria, Australia, as a result of our work.

Keywords

Forensic entomology Maggot mass Computed tomography Volume 

Notes

Acknowledgements

This project was funded by ARC Linkage Grant LP0883711. We thank the Australian Federal Police and the NSW Police Force for their financial support, and the Victorian Institute of Forensic Medicine, the Victoria Police Force and Forensic Science SA for their in-kind support. We are also grateful to Dr. Marijka Batterham (UOW) for her assistance with the statistical analysis of the data.

Ethical Standards

Ethics approval for the use of CT scans of deceased was granted by the ethics committee of the Victorian Institute of Forensic Medicine.

Conflict of interest

The authors declare that they have no conflict of interest.

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Copyright information

© Springer-Verlag 2012

Authors and Affiliations

  • Aidan Johnson
    • 1
  • Melanie Archer
    • 2
  • Lyndie Leigh-Shaw
    • 2
  • Matthew Brown
    • 2
  • Chris O’Donnell
    • 2
  • James Wallman
    • 1
  1. 1.School of Biological SciencesUniversity of WollongongWollongongAustralia
  2. 2.Department of Forensic MedicineMonash University/Victorian Institute of Forensic MedicineSouthbankAustralia

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